A 42-year-old man is facing theft and intentional damage charges after police searched a Rangiora property in Canterbury on Tuesday.
The charges relate to thefts in January and February.
But police are searching for others following a string of incidents, including live wires left exposed near a kindergarten.
Senior Sergeant Roy Appley suspects whoever is doing it might not be thinking straight - the payoff is at best only about $10 a kilogram "and you need an awful lot of it to make a kilogram".
"The people that are often engaged in this sort of activity might not be in full control… they may be suffering from the effects of some drug addiction, and so any reward for any stolen item can be useful in that regard," he told RNZ's Checkpoint programme today.
"So it's not like someone would be going out and thinking, 'What can I do to make a commercial gain that's profitable and will sustain me?' That's not how the people that are doing this would view it."
It is so risky, the fact no one appears to have been killed doing it suggested those involved have some electrical skills, Appley said.
"The equipment that we know that they're using for certain is ... grinding type equipment. That's what's been recovered already, and that's what has been heard by members of the public who have reported it to us.
"There are other items that they're using to isolate the power from the actual copper wire that they're stealing, so that would lead me to believe that whoever is part of this crime has some knowledge of how not to electrocute themselves. It hasn't happened as far as I know."
The thefts began in the residential red zone but have since spread to areas where the electricity is definitely live, he said.
"I don't know the exact voltage that's running through at that stage, but we know when it comes into the property it's certainly enough to knock you off your feet and probably kill you if you're exposed to it without the right equipment.
"So in my view, it's highly dangerous for both the thieves and potentially for any members of the public that might come across it, not know what they're touching."
As for who was buying it, Appley suggested finding them was key to stopping the thefts.
"I don't believe that every scrap metal dealer in Christchurch, for example, is buying this copper wire as it comes in. It's probably limited to a source that we need to identify."
